Do better about getting decent film. 

That sounds like proper mechanics.  Many times the official closest to the play does not have the best angle to make the call because the play is moving away and he's looking though backs.  In those instances, the guy in the middle or even across the field has the much better angle.  Also, as mentioned,  3 sets of eyes to see 22 kids isn't ideal in any way especially when one person is typically focused on the QB the whole time.  Many times we are watching the block you are screaming "holding" about - but there's no real restriction, or looking a hit where you're you're yelling "that's in the back" - but is actually from the side,  and are late getting downfield and into ideal position.